Drill limit system and method of using same

ABSTRACT

A drill limit system includes a holder having drill stops removably coupled thereto and configured to receive a drill bit therethrough, and a platform coupled to the holder and configured to engage a tip end of the drill bits when received through the drill stops, wherein the holder and platform are movable relative to each other so that the position of the drill stops relative to the drill bits may be selectively varied. A method for attaching drill stops to a drill bit includes providing a holder and a platform movable relative to each other, the holder having a plurality of drill stops removably coupled thereto, inserting a plurality of drill bits through respective drill stops, moving the holder and platform relative to each other to select a desired height of the drill stops on the bits, and engaging the drill stops to the drill bits at the selected height.

CROSS REFERENCE TO RELATED CASES

This application is a continuation-in-part of U.S. application Ser. No.15/620,198, filed Jun. 12, 2017, which is a continuation of U.S.application Ser. No. 14/660,408, filed Mar. 17, 2015 (now U.S. Pat. No.9,713,510), which claims the benefit of U.S. Provisional PatentApplication Ser. No. 61/954,440 filed Mar. 17, 2014 and U.S. ProvisionalPatent Application Ser. No. 62/130,905 filed Mar. 10, 2015, thedisclosures of which are incorporated by reference herein in theirentirety.

TECHNICAL FIELD

The present invention relates generally to a drill limit system and,more particularly, to a drill limit system for drilling a bone with adental drill during a medical procedure, such as a dental implantation.

BACKGROUND

Drilling a bone with a drill tends to generate heat within the bone thatmay harm the bone or other surrounding living tissues of a patient.Unfortunately, increased heat often results in an increased risk of harmto the patient. For this reason, a practitioner, such as a dentist,nurse, or other medical professional, traditionally drills the hole soas to reduce the amount of heat generated within the bone. To do so, thepractitioner initially uses a relatively small drill bit for drilling asimilarly small hole in the bone to a desired depth. The practitionerthen uses a relatively larger drill bit for drilling a relatively largerhole coaxially through the smaller hole to the same desired depth. Thepractitioner may then repeat enlarging the hole with additional, largerdrill bits until the hole has a desirable diameter and depth. Byenlarging the hole incrementally with progressively larger drill bits,the practitioner is able to more efficiently and effectively remove aportion of the bone to form the hole with less heat than drillingimmediately with a drill bit having the desired diameter.

While drilling the hole repeatedly, such as during a dental procedure,controlling the drilling depth is crucial to a successful outcome forthe patient. On one hand, drilling the hole too deep may damage tissue,nerves, and/or perforate the sinus cavity of the patient. On the otherhand, drilling the hole too shallow may not provide enough foundation inwhich to secure a dental implant. To increase the likelihood ofrepeatedly drilling the hole to the desired depth, the practitioneroften uses a drill bit having a visual marker and/or a drill stop forindicating a desired drilling depth during the procedure. A drill bitincluding a visual marker for depth may accurately indicate depth, butfails to provide a physical stop to inhibit the practitioner fromdrilling too deep. Also, known drill stops are typically small in sizefor fitment between teeth and may be easily lost or misplaced before,during, or after the dental procedure. In any case, these marked drillbits and drill stops often come in sets for drilling a variety of holesizes, and as such, are expensive to purchase and difficult to handleduring the busy atmosphere of the dental procedure.

Therefore, there is a need for a drill limit system and method fordrilling a bone, such as a tooth and/or jawbone, that addresses presentchallenges and characteristics discussed above.

SUMMARY OF INVENTION

To these ends, a drill limit system for providing a plurality of drillstops with drill bits includes a holder and a platform. The holderincludes a plurality of drill stops removably coupled to the holder andconfigured to receive a drill bit therethrough. The drill stops have afirst state in which the drill bits are configured to be movablerelative to the drill stops and a second state in which the drill stopsare configured to be fixedly secured to the drill bits. The platformincludes a surface configured to engage a tip end of the drill bits. Theholder and the platform are movable relative to each other such that theposition of the drill stops relative to the drill bits may beselectively varied in order to locate the drill stops at a desiredposition on the drill bits.

In one embodiment, the platform is stationary and the holder isconfigured to be movable relative to the platform. In an alternativeembodiment, however, the holder is stationary and the platform isconfigured to be movable relative to the holder. In this embodiment, thedrill limit system may include a rotatable adjustment member such thatrotation of the adjustment member causes movement of the platformrelative to the holder. More particularly, the adjustment member mayinclude a glide element configured to move along a helical groove on theplatform such that rotation of the adjustment member causes the platformto move relative to the holder.

The drill stops are configured to be removably coupled to the holder. Inone embodiment, the holder includes one or more spring clips forselectively engaging the drill stops to and releasing the drill stopsfrom the holder. In this regard, with a sufficient force, the springclips may flex so as to release the drill stop from the holder. Thespring clips may also be configured to all the drill stops to snap backinto engagement with the holder. The spring clips may include one ormore spring fingers or C-springs. The drill stops may include a clipfeature configured to cooperate with the spring clips.

In one embodiment, the drill stops include a nut portion and a gripportion threadably coupled to the nut portion. With such an arrangement,rotation of the nut portion relative to the grip portion transitions thedrill stops between the first and second states. The grip portion mayinclude a clip feature configured to cooperate with one or more springclips on the holder for selectively engaging the drill stops to andreleasing the drill stops from the holder. The holder may include arotatable member configured to rotate the nut portion relative to thegrip portion when the rotatable member is turned. The drill limit systemmay include a torque-control tool configured to engage the nut portionof the drill stop or the rotatable member so as to secure the drillstops to the drill bits.

In another embodiment, a method for attaching drill stops to a drill bitincludes providing a holder and a platform movable relative to eachother, the holder including a plurality of drill stops removably coupledto the holder, inserting a plurality of drill bits through respectivedrill stops in the holder so that a portion of the drill bits engage theplatform, moving the holder and platform relative to each other toselect a desired height of the drill stops on each of the drill bits,and engaging a drill stop onto each of the plurality of drill bits atthe selected height. In one embodiment, the platform is held stationaryand the holder is moved relative to the platform. In an alternativeembodiment, however, the holder is held stationary and the platform ismoved relative to the holder.

The method for attaching drill stops to a drill bit additionallyincludes rotating a first portion of the drill stop relative to a secondportion of the drill stop to engage the drill stop onto each of theplurality of drill bits. Rotating the first portion of the drill stoprelative to the second portion of the drill stop may be accomplished byrotating a rotatable member of the holder that is in contact with thefirst portion of the drill stop

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of this specification, illustrate embodiments of the invention and,together with a general description of the invention given above, andthe detailed description given below serve to explain various aspects ofthe invention.

FIG. 1 is a top perspective view of a drill platform of drill limitsystem according to an embodiment of the invention including a pluralityof drills.

FIG. 2 is a top perspective view of a torque-control tool of the drilllimit system shown in FIG. 1.

FIG. 3 is a front perspective view of the drill platform shown in FIG.1.

FIG. 4A is a front perspective view of a holder of the drill platformshown in FIG. 3.

FIG. 4B is a front perspective view of a base of the drill platformshown in FIG. 3.

FIG. 4C is a front perspective view of a drill stop shown in FIG. 3.

FIG. 5 is an enlarged perspective view of the drill platform shown inFIG. 3 having a pair of flexing elements.

FIG. 6A is a right perspective view of the drill platform shown in FIG.1.

FIG. 6B is a front view of the drill platform shown in FIG. 1.

FIG. 7A is an enlarged perspective view of the torque-control tool, adrill stop, a drill and the drill platform shown in FIG. 1.

FIG. 7B is an enlarged perspective view of the drill stop tightened tothe drill as shown in FIG. 7A.

FIG. 8 is a top perspective view of a drill limit system according to anembodiment of the invention including a plurality of drills.

FIG. 9 is a schematic representation of the drill limit system as shownin FIG. 8.

FIG. 9A is a schematic view of the cap 128 as shown in FIG. 9.

FIG. 9B is a schematic representation of an alternative embodiment of adrill limit system.

FIG. 9C is a schematic representation of the drill limit system as shownin FIG. 9B.

FIG. 10 is a schematic cross-sectional view of the drill limit systemshown in FIG. 8 taken generally along line 10-10.

FIG. 10A is a schematic cross-sectional view of the drill limit systemshown in FIG. 9B.

FIG. 11 is a schematic cross-sectional view of the drill limit systemshown in FIG. 8 taken generally along line 10-10, in which the depthcontrol platform 122 has been raised relative to FIG. 10.

FIG. 12 is a schematic view of the drill bit assembly.

FIG. 12A is a front perspective view of the drill bit assembly shown inFIG. 12 in its assembled state.

FIG. 13 is a schematic view of a portion of an alternative embodiment ofthe drill bit assembly.

FIG. 13A is a schematic view of the portion of an alternative embodimentof the drill bit assembly, as shown in FIG. 13.

FIG. 13B is a schematic cross-sectional view of the view shown in FIG.13A.

FIG. 14 is a schematic cross-sectional view of the drill bit assemblyshown in FIG. 12A taken generally along the 14-14 line.

FIG. 15 is a schematic cross-sectional view of the drill bit assemblyshown in FIG. 12A taken generally along the 15-15 line.

FIG. 16A is schematic view of the torque-control tool of the drill limitsystem shown in FIG. 8, in its disassembled state.

FIG. 16B is a schematic view of the torque-control tool of the drilllimit system shown in FIG. 8, as assembled for use.

FIG. 16C is a schematic view of an alternative embodiment of thetorque-control tool.

FIG. 16D is a schematic view of an alternative embodiment of thetorque-control tool.

FIG. 17 is a schematic cross-sectional view of the drill bit assemblyshown in FIG. 12A taken generally along the 14-14 line with the socketadapter of the torque-control tool shown in FIG. 16B engaged.

FIG. 18 is a schematic cross-sectional view of the drill bit assemblyshown in FIG. 12A taken generally along the 15-15 line with the socketadapter of the torque-control tool shown in FIG. 16B engaged.

FIG. 19 is a perspective view of an exemplary drill limit systemaccording to an alternative embodiment of the invention.

FIG. 20 is an exploded perspective view of the drill limit system ofFIG. 19.

FIG. 21 is a perspective view of the drill limit system of FIG. 19,showing a lid enclosing the drill stops of the drill limit system on theholder.

FIG. 22A is a schematic cross-sectional view of the drill limit systemof FIG. 19, showing the holder at a first height.

FIG. 22B is a schematic cross-sectional view similar to FIG. 22A,showing the holder at a second height.

FIG. 23 is a schematic cross-sectional view showing the torque-controltool engaged with the rotatable socket drive adapter to turn the nutportion of a drill stop of the drill limit system of FIG. 19.

FIG. 24 is a perspective view of an exemplary drill limit systemaccording to an alternative embodiment of the invention.

FIG. 25 is an exploded perspective view of the drill limit system ofFIG. 24.

FIG. 26 is a perspective view of the drill limit system of FIG. 24,showing a lid enclosing the drill stops of the drill limit system on theholder.

FIG. 27A is a schematic cross-sectional view of the drill limit systemof FIG. 24, showing the holder at a first height.

FIG. 27B is a schematic cross-sectional view similar to FIG. 27A,showing the holder at a second height.

FIG. 28A is schematic view similar to FIG. 16A, showing thetorque-control tool aligned with a socket adapter of the drill limitsystem of FIG. 23.

FIG. 28B is a schematic view similar to FIG. 28A, showing thetorque-control tool as assembled for use.

FIG. 29 is a schematic cross-sectional view showing the socket adapterof the torque-control tool shown engaged with the nut portion of a drillstop of the drill limit system of FIG. 24.

DETAILED DESCRIPTION

Although the invention will be described next in connection with certainembodiments, the invention is not limited to practice in any onespecific type of drill limit system. The description of the embodimentsof the invention is intended to cover all alternatives, modifications,and equivalent arrangements as may be included within the spirit andscope of the invention as defined by the appended claims. In particular,those skilled in the art will recognize that the components of theembodiments of the invention described herein could be arranged inmultiple different ways.

With reference to FIGS. 1-4C, a drill limit system 10 for drilling abone, such as a tooth and/or jawbone, during a medical procedure, suchas an osteotomy or other endodontic and dental surgeries, includes adrill platform 12 having a plurality of drill stops 14 and atorque-control tool 16. The drill stops 14 are removably connected to aholder 18 offset from a pedestal 20 for receiving a plurality of drillbits 24 (see FIG. 6B). A practitioner, such as a doctor, nurse, or othermedical professional, moves the holder 18 relative to the pedestal 20 toset a desirable depth for drilling a tooth and/or jawbone with theplurality of drill bits 24, and then positions each of the drill bits 24within a corresponding drill stop 14. Alternatively, the drill bits maybe positioned in a corresponding drill stop 14 and then the holder 18moved relative to the pedestal 20 to set a desired depth. Thetorque-control tool 16 may then be used to tighten each drill stop 14 toeach respective drill bit 24 such that the practitioner may remove andreplace each drill bit 24 with the connected drill stop 14 during themedical procedure. At the conclusion of the medical procedure, thetorque-control tool 16 may be used to loosen each of the drill stops 14from the respective drill bits 24 so that the practitioner may removethe drill bits 24 from the drill platform 12. As such, the drill limitsystem 10 may be cleaned, maintained, or otherwise handled by thepractitioner while the drill stops 14 remain on either the holder 18 orone of the respective drill bits 24 during use. According to anexemplary embodiment, the drill limit system 10 includes eight drillstops 14 arranged proximate to an outer perimeter of the holder 18 forreceiving eight respective drill bits 24 of a variety of diameters. Itwill be appreciated that the holder 18 may be configured to hold anynumber of drill stops 14 for drill bits 24 of any desirable diameter. Inthis respect, the invention is not intended to be limited toaccommodating any particular set of drill bits 24.

As briefly discussed above, the drill platform 12 includes the holder 18for holding the plurality of drill stops 14 and the pedestal 20, whereinthe holder 18 and pedestal are movable relative to each other forsetting a variable depth therebetween (see FIG. 6B). According to anexemplary embodiment, the holder 18 is generally cup-shaped and has agenerally planar endwall 28 and an annular sidewall 30 projectingdownward from the planar endwall 28 toward a base 32 of the pedestal 20when the drill platform is assembled. The pedestal 20 further includes ashaft 34 projecting upward from the base 32. The shaft 34 is configuredfor slidably receiving the holder 18 such that the holder 18 isgenerally free to move upward or downward on or relative to the shaft34. As shown in FIGS. 1-4C, the base 32 is generally planar andconfigured for resting on a relatively flat surface, such as a table,countertop, tray, etc. during the medical procedure for easy access bythe practitioner.

The terms “upward” and “downward” are descriptive terms of oneembodiment of the relative vertical positions of, for example, the base32 to the holder 18. In this respect, the terms “upward” and “downward”are merely exemplary and not intended to limit the invention describedherein. For example, the drill limit system 10 according to anotherexemplary embodiment may be reconfigured for an alternative placementproximate to the practitioner at a generally horizontal or other angledarrangement. Thus, these terms should not limit the present invention toa particular orientation.

With respect to FIGS. 1 and 4A-4B, the shaft 34 is generally cylindricaland further includes a top surface 36, a depth lock 38 projecting from aside 40 of the shaft 34, and a flat surface 42 on the side opposite thedepth lock 38. The depth lock 38 and the flat surface 42 are bothconfigured for cooperating with the holder 18 for setting andmaintaining the position of the drill stops 14 relative to the drillbits 24, as will be discussed below in greater detail. The top surface36 is generally horizontal and includes a plurality of recesses 44configured to receive the drill bits 24 at a uniform vertical positionrelative to the holder 18. In this respect, each recess 44 generallyvertically aligns with a respective drill stop 14, such that each drillbit 24 is held within the holder 18 in a generally vertical orientationand the tips of the drill bits 24 are positioned in the recesses 44.

The holder 18 includes a generally vertical slot 46 extending throughthe annular sidewall 30 defining a pair of opposing inner end walls 48,50. The slot 46 is sized to receive the depth lock 38 such that theinner end walls 48, 50 are vertically movable relative to the depth lock38. More particularly, the inner end walls 48, 50 each include aplurality of depth detents 52 positioned vertically therealong inpredetermined positions for positioning the drill stop 14 relative tothe drill bit 24. Each depth detent 52 is configured to engage the depthlock 38 such that the practitioner may feel, hear, and/or visualize thesetting for enhanced feedback. To further aid the practitioner inmanipulating the holder 18, the holder 18 includes one or more gripsurfaces 54 positioned about the annular sidewall 30.

FIG. 4C shows an exemplary drill stop 14 configured to cooperate withthe holder 18, the drill bits 24, and the torque-control tool 16 ofFIGS. 1-2. The drill stop 14 includes a nut portion 64 configured forbeing received by the torque-control tool 16 and a grip portion 66configured for gripping to a drill bit 24. The nut portion 64, such as alock nut having internal threads and a plurality of external flats 68,is operatively connected to and rotatable relative to the grip portion66, and more particularly externally threaded split fingers, such thatrotating the nut portion 64 in a first direction relative to the gripportion 66 causes the grip portion 66 to reduce in diameter and tightenonto the drill bit 24. This is accomplished by essentially clamping theresilient split fingers of the grip portion 66 onto the drill bit 24.The grip portion 66 also includes a clip feature 70 for removablysecuring the drill stop 14 to the holder 18, as discussed below. In anexemplary embodiment, the clip feature 70 may be configured as anannular ring protruding outward from the grip portion 66. In addition,the grip portion 66 includes a pair of opposing grooves 72 in a bottomsurface of the grip portion 66, the purpose of which will be describedbelow.

As discussed briefly above and with respect to FIGS. 4A-5, the planarendwall 28 of holder 18 includes a plurality of holes 56 for receivingthe drill stops 14 and, in turn, the drill bits 24 (see FIG. 1).According to an exemplary embodiment, holes 56 extend vertically throughthe planar endwall 28 toward the top surface 36 of the shaft 34proximate to the outer perimeter of the holder 18. For each of the holes56, the planar endwall 28 further includes a pair of opposing recesses58 extending into the hole 56 and a pair of opposing abutments 60projecting upward from the planar endwall 28 adjacent to the hole 56(see FIG. 5). More particularly, the abutments 60 and recesses 58 may beapproximately 90 degrees offset from each other. Each recess 58 includesan L- or J-shaped spring clip 62 extending from the planar endwall 28,such as via a separate element mounted on an underside surface ofendwall 28 or integrally formed with endwall 28, adjacent to the hole56. The spring clip 62 is configured to removably engage the drill stop14 concentrically about the hole 56 via clip feature 70 of grip portion66. While an exemplary embodiment includes spring clips 62 for removablyconnecting the drill stops 14 to the planar endwall 28, it will beappreciated that another structure for removably connecting the drillstop 14 to the planar endwall 28 about the hole 56 may be similarlyused. Once the drill stop 14 is positioned relative to the hole 56, eachabutment 60 cooperatively engages the opposing grooves 72 of drill stop14 to inhibit rotation of the grip portion 66 while the nut portion 64rotates, thereby tightening (or loosening) the drill stops 14 to thedrill bits 24.

In accordance with the invention, the practitioner manipulates thetorque-control tool 16 in order to tighten and/or loosen the drill stop14 relative to the drill bit 24. The torque-control tool 16 includes ahandle 74 for the practitioner to grip and a rotatably connected socketwheel 76. The handle 74 extends to a detent end 78, which receives thesocket wheel 76 similar to that of a pinwheel. The socket wheel 76includes a plurality of radial projections 80, or spokes, projectingoutward from a central portion of the socket wheel 76. Each radialprojection 80 includes a socket hole 82 sized to receive the flats 68 ofthe nut portion 64 discussed above. According to an exemplaryembodiment, the socket wheel 76 includes eight projections 80 withsocket holes 82 sized to correspond to the eight drill bits 24 discussedabove. However, it will be appreciated that the number of theprojections 80 may vary in accordance with the number of drill bits 24and drill stops 14 to be used with the system 10.

To select the desired projection 80 for the desired drill stop 14, thepractitioner rotates the socket wheel 76 such that the projection 80 isaxially aligned with and projecting away from the handle 74. Inaddition, the socket wheel 76 includes a torque limit mechanism in whichthe socket wheel 76 is biased, such as with a spring (not shown) withinthe detent end 78 to hold the socket wheel 76 in such an alignedposition up to a desired amount of torque. For example, the practitionermay tighten the nut portion 64 of the drill stop 14 until the desiredamount of torque is reached, at which point the socket wheel 76 ratchetsfree of the biased alignment to indicate to the practitioner that thenut portion 64 is sufficiently tightened. According to an exemplaryembodiment, an exemplary desired amount of torque may be approximately60 Ncm. Of course, this torque value may vary depending on theparticular application. As such, the biased ratcheting of the socketwheel 76 further inhibits the practitioner from over tightening, whichmay damage the drill stop 14, and from under tightening, which mayresult in the drill stop 14 coming loose during use.

In use, FIGS. 6A-6B show the drill platform 12 having the drill bits 24resting loosely within the drill stops 14. The practitioner loosens alocking element 84 from against the flat surface 42 of the side of theshaft 34. The locking element 84, such as a set screw, threadablyengages the annular sidewall 30 of the holder 18 and remains in theholder 18 once the locking element 84 is loosened. With the lockingelement 84 loosened, the holder 18 is movable vertically upward anddownward relative to the top surface 36 of the shaft 34 to define thevariable depth therebetween, i.e. between endwall 28 and top surface 36of shaft 34. As shown in FIG. 6B, an exemplary embodiment of the depthlock 38 includes a pair of opposing biased pins 86 that engage thepredetermined depth detents 52 for setting the variable depth. Aplurality of numerals positioned adjacent to each depth detent 52indicate a corresponding depth to which the drill bits 24 will beremovably connected to the drill stops 14. When a desirable depth isselected, the practitioner tightens the locking element 84 against theshaft 34 to lock the holder 18 relative to the shaft 34.

With respect to FIGS. 7A-7B, the practitioner selects the correspondingprojection 80 of the socket wheel 76 and slides the socket hole 82 ontothe drill bit 24 until the socket hole 82 engages the flats 68 of thenut portion 64. The practitioner manipulates the handle 74 to rotate thenut portion 64 relative to the grip portion 66 to clamp the grip portion66 onto the drill bit 24. Once the drill stop 14 is connected to thedrill bit 24, the socket wheel 76 ratchets free to indicate that anappropriate amount of torque has been applied to the drill stop 14. Thepractitioner repeats this tightening for each of the drill stops 14 andcorresponding drill bits 24 in the drill platform 12.

From the smallest diameter drill to the largest diameter drill necessaryto drill a desirable hole in the bone, the practitioner forms the holeby disengaging the drill bit 24 from the holder 18. To disengage thedrill bit 24 from the holder 18, the practitioner pulls the drill bit 24generally upwardly with sufficient force to overcome the hold of thespring clip 62 to the clip feature 70 of grip portion 66. Thepractitioner then drills a hole in the bone with the drill bit 24 to thedesired depth, as indicated by the drill stop 14, and then replaces thedrill stop 14 and drill bit 24 back into its corresponding hole 56 andreengaging the spring clip 62 and spring feature 70. The practitionerrepeats this disengaging, drilling, and replacing of the drill stops 14and drill bits 24 until the hole in the bone is at the desirablediameter and at the desired depth as determined by the drill stops 14.

Once the hole in the bone is complete, the practitioner loosens each ofthe drill stops 14 from the drill bits 24 as discussed above, andremoves the drill bits 24 from the drill platform 12. The lockingelement 84 is then loosened from the shaft 34, and the holder 18,including the drill stops 14, is removed from the shaft 34 for cleaningand other routine maintenance in order to prepare the drill limit system10 for another medical procedure.

FIGS. 8-18 show alternative embodiments of the drill limit system, wherelike labels indicate similar components. As best shown in FIGS. 8 and 9,drill limit system 110 includes a drill platform 112 and atorque-control tool 116. The drill platform 112 includes holder portion118, depth control portion 119, and pedestal 120.

Pedestal 120 is composed of base 132 and shaft 134. Base 132 containsspecially adapted recesses 121 a and 121 b for receiving thetorque-control tool 116 and is generally planar and configured forresting on a relatively flat surface, such as a table, countertop, tray,etc. during the medical procedure for easy access by the practitioner.Shaft 134 is generally cylindrical, projecting away from the base 132,and is configured for slidably receiving the depth control portion 119such that the depth control portion 119 is generally free to move in acertain direction on the shaft 134, which is shown as a verticaldirection in the figures. The shaft 134 contains an upper portion thatprojects beyond the depth control portion 119 and interacts with holderportion 118 through threaded through-hole 111 and bore 113, which aredescribed in greater detail below.

Depth control portion 119 is composed of variable depth platform 122,which fits over shaft 134, depth control member 115, and indicator ring129. Variable depth platform 122 is composed of top surface 136, havinga plurality of recesses 144 configured to receive the tip of drill bits124, and an annular sidewall 117, which contains helical grooves 123 anddepth notches 152. Depth control member 115, which is configured tointeract with variable depth platform 122 in a manner discussed morefully below, is composed of a top surface 125 with a raised joining ringmember 127 and an annular sidewall 195. Raised joining ring member 127is configured to interact with cap 128 of the holder portion 118. Theindicator ring 129 fits over the depth control member 115 and contains aplurality of grip features 154 to aid the practitioner in turning thedepth control member 115, as well as a plurality of indicia of depth131.

Holder portion 118 is composed of bottom plate 133, upper plate 135,flexing element 162, rotatable socket drive adapter 167, and cap 128.The drill bits 124 and drill stops 114 rest within holder portion 118when not in use during the medical procedure. Bottom plate 133 and upperplate 135 possess an annular geometry of substantially equal diameter.However, bottom plate 133 includes a plurality of guide protrusions 139configured to fit within openings 156 of cap 128 and to rest in ridges126 of cap 128. Bottom plate 133 also contains one or more tabs 141,which can be used for inserting bottom plate 133 into the ridges 126, aswell as one or more threaded holes 143 a configured to align bottomplate 133 with upper plate 135 and cap 128. Bottom plate 133 has acenter hole 147 a and a plurality of openings 149 at least as large asthe diameter of the drill bit 124. Upper plate 135 also includes one ormore holes 143 b configured to align upper plate 135 to bottom plate 133and cap 128, as well as center hole 147 b. The cap 128, upper plate 135,and bottom plate 133, are held in contact with ball bearing set screw145. Flexing element 162 is configured to fit within a plurality offlexing element alignment openings 151 of upper plate 135, whichgenerally align with openings 149 of the bottom plate 133. The number ofbottom plate openings 149 and upper plate flexing element alignmentopenings 151 is determined by the number of drill bits 124 and drillstops 114 desired. In the figures, eight drill bits 124 and drill stops114 are shown, but the invention is not so limited. The rotatable socketdrive adapter 167 has an annular base 169, with a diameter greater thanthe corresponding opening 156 in cap 128, and wings 171. The rotatablesocket drive adapter 167, which rests on upper plate 135, is placed overflexing element 162.

Conveniently, one or both of the flexing element 162 and the rotatablesocket drive adapter 167 may be color coded to quickly indicate to thepractitioner the matching sets of components. Additionally, a pluralityof indicia 153 may be printed, etched, or otherwise included, proximateto the flexing element alignment openings 151 of upper plate 135 toindicate to the practitioner the diameter of the drill bit 124 housed ateach flexing element alignment opening 151.

Cap 128 is composed of a top surface 155 and annular sidewall 157. Topsurface 155 of cap 128 contains a plurality of openings 156, whichgenerally align with flexing element alignment openings 151 of upperplate 135 and the openings 149 and guide protrusions 139 of bottom plate133. The annular sidewall 157 of cap 128 includes indicia 159 configuredto align with the appropriate indicia of depth 131 of depth controlmember 115 when the drill limit system is in use, the mode of which isdescribed in further detail below. On the obverse side of top surface155, as shown in FIG. 9A, cap 128 contains securing portion 161, whichis generally cylindrical but may contain an aligning feature, such asflat surface 163 shown. To assemble the holder portion, securing portion161 passes through the center holes 147 b, 147 a of upper and bottomplates 135, 133. The tabs 141 are then used to rotate the bottom plate133 such that the guide protrusions 139 engage with ridges 126 andgenerally align with openings 156. The securing portion 161 can then bepassed through depth control member 115 and variable depth platform 122,into a complementary bore 113 of shaft 134. Spring-loaded biased pins165 may be used to secure the securing portion 161 of cap 128 to theshaft (see FIGS. 10 and 11).

As best shown in FIGS. 12, 12A, and 14-15, drill stop 114 is composed ofnut portion 164, including internal threads and a plurality of flats168, and grip portion 166 with a clip feature 170. Nut portion 164 andgrip portion 166 both have an internal diameter slightly larger than theouter diameter of the drill bit 124. The drill bit 124 is passed throughthe inner diameter of the nut portion 164 and grip portion 166 withinthe rotatable socket drive adapter 167 and flexing element 162 of holderportion 118, with the tip 173 of drill bit 124 resting in recess 144 ofthe top surface 136 of variable depth platform 122. When drill stop 114comes in contact with flexing element 162, resilient fingers 175 engageclip feature 170 of grip portion 166.

Torque-control tool 116, as best shown in FIGS. 16A and 16B, is composedof two parts: ratchet 179 and socket adapter 181. When not in use, thetorque-control tool 116 may conveniently rest in specially adaptedrecesses 121 a, 121 b on pedestal 120. In use, socket adapter 181 iscomposed of connecting end 183, which includes fitment 185 configured tointeract with ratchet 179, and torque end 187, which includes slots 189configured to interact with wings 171 of rotatable socket drive adapter167. Ratchet 179 includes a handle end 174 and a connecting end 190configured to interact with fitment 185 of connecting end 183 of socketadapter 181. Handle end 174 includes a torque-control member 191, whichcan be used to set a desired torque value. Such torque limit mechanismsand ratchets are known in the art and will not be discussed in furtherdetail.

Alternatively, torque-control tool 216 is shown in FIG. 16C, andtorque-control tool 316 is shown in FIG. 16D. Both include a handleportion 274, 374, and a torque end 287, 387. The torque ends 287, 387are attached to handle portion 274, 374, through hinge portion 283, 383,which allows the handle portion 274, 374, to swivel relative to thetorque end 287, 387. This ability to swivel may, for example, allow thepractitioner better grip and control on the torque-control tool 216,316. Also, the hinge portion 283, 383 may include a torque limitmechanism. Each of the disclosed embodiments of the drill limit system110, 210 may use any of the torque-control tools 116, 216, 316, inprinciple.

FIGS. 9B, 9C, 10A, 13, 13A, and 13B, show an alternative embodiment ofthe drill limit system 210, where like labels indicate similarcomponents. The drill limit system 210 includes a drill platform 212 anda torque-control tool 216. The drill platform 212 includes holderportion 218, depth control portion 219, and pedestal 220.

Pedestal 220 is composed of base 232 and shaft 234. Base 232 containsspecially adapted recesses 221 a and 221 b and is generally planar andconfigured for resting on a relatively flat surface, such as a table,countertop, tray, etc. during the medical procedure for easy access bythe practitioner. Shaft 234 is generally cylindrical, projecting awayfrom the base 232, and is configured for slidably receiving the depthcontrol portion 219 such that the depth control portion 219 is generallyfree to move in a certain direction on the shaft 234, which is shown asa vertical direction in the figures. The shaft 234 is held to pedestal220 via bolt 296.

Depth control portion 219 is composed of variable depth platform 222,which fits over shaft 234, depth control member 215, and indicator ring229. Variable depth platform 222 is composed of top surface 236, havinga plurality of recesses 244 configured to receive the tip 273 of drillbits 224, and an annular sidewall 217, which contains helical groove 223and depth notches 252. Depth control member 215, which is configured tointeract with variable depth platform 222 in the same manner asdiscussed above for depth control member 115 (i.e., an interactionbetween glide elements 292 and the helical groove 223), is composed of atop surface 225 with a raised joining ring member 227 and an annularsidewall 295. Raised joining ring member 227 is configured to interactwith cap 228 of the holder portion 218. The indicator ring 229 fits overthe depth control member 215 and contains a plurality of grip features254 to aid the practitioner in turning the depth control member 215, aswell as a plurality of indicia of depth 231.

Holder portion 218 is composed of bottom plate 233, upper plate 235,flexing element 262, rotatable socket drive adapter 267, and cap 228.The drill bits 224 and drill stops 214 rest within holder portion 218when not in use during the medical procedure. Bottom plate 233 and upperplate 235 possess an annular geometry of substantially equal diameter.Bottom plate 233 has a center hole 247 a and a plurality of openings 249at least as large as the diameter of the drill bit 224. Upper plate 235also includes center hole 247 b. The cap 228, upper plate 235, andbottom plate 233, are held in contact via tabs 245 of cap 228 andopenings 297 a, 297 b. Flexing element 262 is configured to fit within aplurality of flexing element alignment openings 251 of upper plate 235,which generally align with openings 249 of the bottom plate 233. Thenumber of bottom plate openings 249 and upper plate flexing elementalignment openings 251 is determined by the number of drill bits 224 anddrill stops 214 desired. In the figures, eight drill bits 224 and drillstops 214 are shown, but the invention is not so limited. Although drilllimit systems 110 and 210 share many similarities, as best shown inFIGS. 13-13B, a difference between the two drill limit systems, is thatin flexing element 262, C-spring 275, as opposed to resilient fingers175, is used to removably connect grip portion 266 to holder portion218, through ring grooves 270. In this manner, the drill bit 224 anddrill stop 214 can be removed from and replaced on flexing element 262with ease. Rotatable socket drive adapter 267 functions in a similarmanner to rotatable socket drive adapter 167. As discussed above,torque-control tools 116, 216, and 316, are interchangeable within thevarious disclosed embodiments.

Conveniently, one or both of the flexing element 262 and the rotatablesocket drive adapter 267 may be color coded to quickly indicate to thepractitioner the matching sets of components. Additionally, a pluralityof indicia 253 may be printed, etched, or otherwise included, proximateto the flexing element alignment openings 251 of upper plate 235 toindicate to the practitioner the diameter of the drill bit 224 housed ateach flexing element alignment opening 251.

Cap 228 is composed of a top surface 255 and annular sidewall 257. Topsurface 255 of cap 228 contains a plurality of holes 256, whichgenerally align with flexing element alignment openings 251 of upperplate 235 and the openings 249 of bottom plate 233. Top surface 255 ofcap 228 also includes opening 298. The annular sidewall 257 of cap 228includes indicia 259 configured to align with the appropriate indicia ofdepth 231 of indicator ring 229 when the drill limit system is in use,the mode of which is similar to that of drill limit system 110 describedabove. When attaching the holder portion 218 to the depth controlportion 219 and the pedestal 220, the shaft 265 of joining member 261 ispassed through depth control portion 219 and affixed to shaft 234 withthreaded bolt receiver 299. Threaded bolt receiver 299 includes an innerthreaded surface and an outer threaded surface. The inner threadedsurface attaches to bolt 296. Shaft 265, in turn, includes threadingcomplementary to the outer threaded surface of threaded bolt receiver299. Once the joining member 261 is affixed to the shaft 234, the bottomplate 133, upper plate 135, and cap 228, are affixed to joining member261 and held in place by clips 263 and opening 298. Thus, removing theholder portion 218 from the drill limit system 210 is easilyaccomplished by pinching together clips 263 and lifting the holderportion 218 away from the depth control portion 219.

Turning now to the operation of drill limit system 110, the practitionerplaces the drill stop 114 in the appropriate location of the holderportion 118 and then passes drill bit 124 through drill stop 114. Thedrill bit 124 is freely moveable in the same direction as the variabledepth platform 122, which is shown as the vertical direction in thefigures, until the nut portion 164 is rotated to clamp the grip portion166 onto the drill bit 124. Because drill bit 124 is freely moveable,the tip 173 of the drill bit 124 rests in recess 144 of the top surface136 of variable depth platform 122 at a uniform vertical positionrelative to the holder portion 118. In this respect, each recess 144generally vertically aligns with a respective drill stop 114, such thateach drill bit 124 is held within the holder portion 118 in a generallyvertical orientation.

To set the height of the drill stop 114, the practitioner rotates theindicator ring 129 to the desired height as indicated by aligningindicia 159 of annular sidewall 157 of cap 128 with the appropriateindicia of depth 131 of indicator ring 129. The rotation of indicatorring 129 rotates depth control member 115. As best shown in FIGS. 10 and11, glide element 192 on the inside surface 193 of annular sidewall 195of depth control member 115 rides along helical groove 123 as the depthcontrol member 115 is rotated to the desired height setting. The glideelement 192 may be, for example, a biased pin or a ball bearing. Depthnotches 152, which interact with one of the glide elements 192 on theinside surface 193 of annular sidewall 195 of depth control member 115,provide a tactile and audible indication that the height indicated bythe appropriate indicia of depth 131 has been reached. However, thepractitioner may rotate the depth control member 115 to be slightly moreor slightly less than the indicated height to allow fine control of theheight of drill stop 114. As the depth control member 115 is rotated,the motion of the glide element 192 in helical groove 123 raises orlowers the variable depth platform 122, which in turn raises or lowersthe drill bit 124. As opposed to drill limit system 10, in drill limitsystem 110, the variable depth platform 122 moves relative to the base132 while the holder portion 118 is stationary relative to the base 132.As described above, drill bit 124 is freely moveable in the samedirection as the variable depth platform 122.

Once the desired height has been set, torque-control tool 116, assembledas described above, is used to turn rotatable socket drive adapter 167.As rotatable socket drive adapter 167 is turned, due to its contact withflats 168 of nut portion 164, the movement causes turning of nut portion164 with the grip portion 166 remaining stationary due to itsinteraction with flexing element 162. In this manner, nut portion 164,and more particularly the resilient split fingers thereof, can tightenand loosen grip portion 166 on drill bit 124, as best shown in FIGS. 17and 18. Tightening occurs until a preselected torque value, as set usingtorque-control member 191, is reached, at which point connecting end 190of ratchet 179 ratchets free and will no longer tighten the nut portion164. This process is repeated for each of the drill stops 114 andcorresponding drill bits 124 in the drill platform 112.

Once the grip portion 166 is tightened to drill bit 124, the drill bit124 is ready for use. As described above, drill bit 124 with drill stop114 is placed within flexing element 162 and held in a generallyvertical orientation via resilient fingers 175, which engage clipfeature 170 of grip portion 166. The practitioner removes the drill bits124 from the smallest diameter drill bit to the largest diameter drillbit necessary to drill a desired hole in the bone. Drill bit 124 maycoupled to a dental drill (not shown) and disengaged from the holderportion 118, by overcoming the force of the interaction between theresilient fingers 175 and clip feature 170. In this manner, thepractitioner never needs to touch the drill bits 124 during theprocedure. The hole in the bone is drilled with the drill bit 124 to thedesirable depth as indicated by the drill stop 114. After the depth ofthe hole is such that the edge of the drill stop is reached, thepractitioner removes the drill from the hole and replaces the drill bit124 into its corresponding opening 156 until the resilient fingers 175reengage the clip feature 170 of grip portion 166 to secure the drillbit 24 to the holder portion 118. The practitioner repeats thisdisengaging, drilling, and replacing of the drill bits 124 with drillstops 114 until the hole in the bone is the desired diameter.

Once the hole in the bone is complete, the practitioner loosens each ofthe drill stops 114 from the drill bits 124 using the torque-controltool as discussed above, and removes the drill bits 124 from the drillplatform 112. The drill limit system 110 can then be disassembled forcleaning and other routine maintenance in order to prepare the drilllimit system 110 for another medical procedure.

In principle, drill limit system 210 operates similarly to drill limitsystem 110. The height of the drill bits 224 is set simultaneously bysetting the depth control portion 219 to the desired height. Then thedrill stop 214 is engaged with drill bit 224 by rotating rotatablesocket drive adapter 267, which in turn rotates nut portion 264,ultimately causing grip portion 266 to grip the drill bit 224. The drillbits 224 are then removed from the holder portion 218 by disengagingring grooves 270 of grip portion 266 of drill stop 214 from the flexingelement 262, working from the smallest diameter drill bit to the largestdesired diameter drill bit. In this manner, a hole may be drilled in abone to a desired depth without overheating the bone.

Referring now to FIGS. 19-22B, in an alternative embodiment, a drilllimit system 410 includes a holder 412 movably coupled to a pedestal 414for setting a variable depth therebetween. As best shown in FIG. 20, theholder 412 is generally cup-shaped and has a generally planar endwall420 and an annular sidewall 422 projecting downward from the planarendwall 420. The planar endwall 420 includes a plurality of bores 424for receiving a plurality of drill bits 430. To that end, the bores 424may each have a cross sectional dimension equal to or greater than thediameter of the corresponding drill bit 430 and less than a crossdimension of the corresponding drill stop 432, so that each drill stop432 may rest on the planar endwall 420. The drill bits 430 and drillstops 432 may be substantially similar to those described above withrespect to FIGS. 9, 10, 11, and 12, for example. As shown, the planarendwall 420 further includes a central hole 440 and a plurality ofgenerally rectangular apertures 442 at or near a periphery of the planarendwall 420, as well as a plurality of pinholes 444 and/or pin slot(s)446 distributed about the central hole 440. In one embodiment, thecentral hole 440 may be configured to receive a torque-control tool 448of the system 410.

In the embodiment shown, the planar endwall 420 of the holder 412 ispositioned below, or offset from, an upper end of the generally annularsidewall 422 to provide a recessed area 450 for receiving generallyannular bottom and upper plates 452, 454 which are fixed to the holder412 against movement relative thereto. In this regard, the bottom plate452 includes a plurality of notches 456 configured for alignment withthe apertures 442 of the planar endwall 420, and the upper plate 454includes a plurality of tabs 458 configured to extend through thenotches 456 and into the apertures 442, thereby sandwiching the bottomplate 452 between the upper plate 454 and the planar endwall 420. In theembodiment shown, the bottom plate 452 also includes a plurality of pinholes 460 and a pin slot 462 configured for alignment with the pin holes444 and pin slot 446 of the planar endwall 420, respectively, and theupper plate 454 includes at least one pin 464 configured for alignmentwith and insertion in the corresponding pin holes 444, 460 and/or pinslots 446, 462 of the planar endwall 420 and bottom plate 452. In thismanner, the pin holes 444, 460, pin slots 446, 462, and/or pins 464 mayprovide a desired orientation of the upper plate 454, bottom plate 452,and planar endwall 420 relative to each other.

The bottom plate 452 includes a central hole 470 for receiving thetorque-control tool 448 and a plurality of openings 472 for receivingthe drill stops 432. As shown, the openings 472 may each have agenerally hexagonal cross section in order to provide a close fitagainst the flats 474 of the grip portions 476 of the respective drillstops 432. However, it will be appreciated that other configurations arepossible without departing from the scope of the invention.

The upper plate 454 includes a central hole 478 for receiving thetorque-control tool 448. In the embodiment shown, a plurality ofrotatable socket drive adapters 480 similar to those discussed above areprovided for the plurality of drill stops 432. In this regard, the upperplate 454 includes a plurality of rotatable socket drive adapteropenings 482 having generally circular cross sections and aligned withthe openings 472 of the bottom plate 452. Each rotatable socket driveadapter opening 482 includes at least one lip 484 extending radiallyinwardly from the periphery of the opening 482. The annular base 486 ofeach rotatable socket drive adapter 480 is positioned between the lip(s)484 of the corresponding opening 482 and the bottom plate 452 such thatthe rotatable socket drive adapter 480 may rest on the bottom plate 452.In this manner, each rotatable socket drive adapter 480 may be rotatablysecured to the holder 412.

Conveniently, the rotatable socket drive adapter 480 may be color codedto quickly indicate to the practitioner the matching sets of components.Additionally, a plurality of indicia 488 may be printed, etched, orotherwise included, proximate to the rotatable socket drive adapteropenings 482 of the upper plate 454 to indicate to the practitioner thediameter of the drill bit 430 housed at each rotatable socket driveadapter opening 482.

As shown, the holder 412 further includes a plurality of generallyvertical slots 490 extending through the generally annular sidewall 422and a plurality of indicia of depth 492 adjacent each vertical slot 490.In the embodiment shown, the annular sidewall 422 of the holder 412includes one or more grip surfaces 494 to aid the practitioner inmanipulating the holder 412. The annular sidewall 422 further includes athreaded inner surface 496 which may include, for example, a helicalgroove 498, for reasons discussed below.

The illustrated pedestal 414 includes a base 500 and a generallycylindrical shaft 502 projecting upward from the base 500 to an upperend 504. The base 500 may include one or more feet 506 (FIG. 22A) forsupporting the pedestal 414 on a surface, such as a table (not shown).The shaft 502 is configured for rotatably receiving the holder 412 suchthat the holder 412 is generally free to rotate on or relative to theshaft 502 so as to cause vertical movement of the holder 412 on orrelative to the shaft 502. To that end, the shaft 502 includes athreaded outer surface 510 for threadably engaging the threaded innersurface 496 of the annular sidewall 422 of the holder 412. For example,the threaded outer surface 510 may include a plurality of projections512 extending along a helical path and configured to engage the helicalgroove 498 of the threaded inner surface 496 of the holder 412. In anyevent, the interaction of the threaded outer surface 510 with thethreaded inner surface 496 translates the turning motion of the holder412 relative to the shaft 502 into linear motion of the holder 412relative to the shaft 502. For example, clockwise rotation of the holder412 relative to the shaft 502 may move the holder 412 in a downwarddirection relative to the shaft 502, and counterclockwise rotation ofthe holder 412 relative to the shaft 502 may move the holder 412 in anupward direction relative to the shaft 502, or vice versa. Theillustrated shaft 502 further includes two pairs of vertical slots 514extending from the upper end 504 toward the base 500 to form twooppositely disposed tab portions 516 of the shaft 502. A stopper 518extends radially from each tab portion 516 for limiting the rotationalmovement of the holder 412 relative to the shaft 502 to prevent theholder 412 from being disengaged from the shaft 502. Thus, the movementof the holder 412 relative to the shaft 502 may be bounded between anupper limit defined by the stoppers 518 and a lower limit defined by thebase 500. The tab portions 516 may be flexible such that undersufficient force, the tab portions 516 may be flexed radially inwardlyto allow the threaded inner surface 496 of the holder 412 to pass freelyabout the stoppers 518, such as during assembly or disassembly of thedrill limit system 410.

The illustrated drill limit system 410 further includes a platform 520rotatably positioned over the upper end 504 of the shaft 502 of thepedestal 414. The platform 520 may rest atop the shaft 502 below theendwall 420 of the holder 412 such that the platform 520 may begenerally vertically stationary with respect to the shaft 502 during useof the drill limit system 410. Thus, vertical movement of the holder 412relative to the shaft 502 also causes vertical movement of the holder412 relative to the platform 520. In this manner, rotation of the holder412 relative to the shaft 502 may set the variable depth of the holder412 relative to the platform 520.

As shown, the platform 520 includes a generally circular top surface 522and a plurality of fingers extending radially outwardly from a peripheryof the top surface 522, including an engagement finger 524 and aplurality of marker fingers 526. The top surface 522 is generallyhorizontal and includes a center hole 528 and a plurality of recesses530 configured to receive the drill bits 430 at a uniform verticalposition relative to the platform 520. In this respect, each recess 530generally vertically aligns with a respective drill stop 432, such thateach drill bit 430 is held within the corresponding bore 440 of theholder 412 in a generally vertical orientation and the tip of each drillbit 430 is positioned in the corresponding recess 530 of the platform520. In the embodiment shown, the top surface 522 further includes anannular groove 532 at or near the periphery of the top surface 522. Theannular groove 532 may provide clearance for the tabs 458 of the upperplate 454 when coupled to the holder 412 (FIG. 22A).

The engagement finger 524 of the platform 520 is configured tomechanically engage a generally vertical channel 540 extending along thethreaded inner surface 496 of the annular sidewall 422 of the holder412, in order to cause the platform 520 to rotate with rotation of theholder 412 relative to the shaft 502. In this regard, the platform 520includes a generally annular bearing surface 542 on an underside of theplatform 520 opposite the top surface 522 for rotatably engaging theupper end 504 of the shaft 502 to enable the platform 520 to generallyfreely rotate on the shaft 502. In one embodiment, the engagement finger524 and vertical channel 540 are each sized and shaped to provide atight fit therebetween for precise rotation of the platform 520 with theholder 412. It will be appreciated that by rotating the platform 520with the rotation of the holder 412, the alignment of the recesses 530of the platform 520 with the corresponding bores 424 of the holder 412,and/or openings 472, 482 of the bottom and upper plates 452, 454 may bemaintained during rotation of the holder 412. Thus, the drill bits 430may remain in place in the drill limit system 410 while the variabledepth between the platform 520 and holder 412 is set.

The marker fingers 526 of the platform 520 are configured to extendthrough the vertical slots 490 of the holder 412 and align with thecorresponding indicia of depth 492 on the holder 412 to provide a visualindication of a current variable depth between the platform 520 and theholder 412. For example, as the holder 412 is rotated relative to theshaft 502, thereby adjusting the variable depth between the platform 520and holder 412, the indicia of depth 492 move vertically relative to therespective marker fingers 526, which remain generally verticallystationary. Thus, the alignment of a marker finger 526 with a particularindicia of depth 492 may correspond to a certain variable depth betweenthe platform 520 and holder 412.

As shown in FIG. 21, the drill limit system 410 includes a lid 550 whichmay be removably secured to the holder 412 over the upper plate 454. Thelid 550 includes a generally circular cover portion 552 and a pluralityof locking tabs 554 extending downward at or near the periphery of thecover portion 552. The locking tabs 554 are configured to engage one ormore features of the holder 412 in order to retain the lid 550 on theholder 412. In the embodiment shown, the locking tabs 554 are configuredto engage with upper portions of the vertical slots 490 of the holder412. In one embodiment, the locking tabs 554 may be configured toprovide a snap-fit engagement with the vertical slots 490. In thisregard, the locking tabs 554 and/or cover portion 552 may comprise asemi-flexible material, such as a plastic material, so that under asufficient force the locking tabs 554 may snap into place to secure thelid 550 to the holder 412, and so that under a sufficient force thelocking tabs 554 may be unsnapped to remove the lid 550 from the holder412. Apertures 556 may be provided in the lid 550 adjacent the lockingtabs 554 to provide flexibility thereto. In this manner, the lid 550 mayprevent the drill stops 432 and/or other components from being dislodgedfrom the holder 412 and/or lost, such as during transportation of thedrill limit system 410.

With specific reference now to FIGS. 22A and 22B, to set the height ofthe drill stops 432 relative to the corresponding drill bits 430, thepractitioner rotates the holder 412 to the desired height as indicatedby aligning the marker fingers 526 of the platform 520 with theappropriate indicia 492 of the holder 412. For example, the practitionermay rotate the holder 412 from a first height (FIG. 22A) to a secondheight (FIG. 22B). As described above, as the holder 412 is rotated, thethreadable engagement of the threaded inner surface 496 of the holder412 with the threaded outer surface 510 of the shaft 502 raises orlowers the holder 412 relative to the platform 520, which in turn raisesor lowers the drill stops 432 relative to the drill bits 430.

As shown in FIG. 23, once the desired height of a drill stop 432 hasbeen set, the torque-control tool 448, which may be stored in thecentral openings 440, 470, 478, 582 of the holder 412, bottom plate 452,upper plate 454, and platform 520, and/or within an interior of theshaft 502, may be used to secure the drill stop 432 to, or remove thedrill stop 432 from, the respective drill bit 430 using thecorresponding rotatable socket drive adapter 480, in a manner similar tothat described with respect to FIGS. 17 and 18. While not described indetail, the various features of the torque-control tool 448 aresubstantially similar in structure and/or function to those of theaforementioned torque-control tools 116, 216, and 316, such that thetorque-control tool 448 is interchangeable therewith. In any event, asthe rotatable socket drive adapter 480 is turned, due to its contactwith the flats 560 of the nut portion 562, the movement causes turningof the nut portion 562 with the grip portion 476 remaining stationarydue to its interaction with the openings 472 of the bottom plate 452 ofthe holder 412. In addition or alternatively, spring clips and/or clipfeatures similar to those described above may be used to retain the gripportion 476 on the holder 412. In any event, the nut portion 562 maytighten and loosen the grip portion 476 on the drill bit 430 in a mannersimilar to that described with respect to the above embodiments.

Referring now to FIGS. 24-29, in an alternative embodiment, a drilllimit system 610 includes a holder 612 movably coupled to a pedestal 614for setting a variable depth therebetween. As best shown in FIG. 25, theholder 612 is generally cup-shaped and has a generally planar endwall620 and an annular sidewall 622 projecting downward from the planarendwall 620. The planar endwall 620 includes a plurality of bores 624and corresponding recesses 626 for receiving a plurality of drill bits630, and drill stops 632, respectively. The drill bits 630 and drillstops 632 may be substantially similar to those described above withrespect to FIGS. 9, 10, 11, and 12, for example. As shown, the recesses626 may be similar to counterbores having generally hexagonal, ratherthan circular, cross sections in order to provide a close fit againstthe flats 640 of the grip portions 642 of the respective drill stops632. However, it will be appreciated that other configurations arepossible without departing from the scope of the invention. As shown, aplurality of indicia 644 may be printed, etched, or otherwise included,proximate to the bores 624 and/or recesses 626 of the planar endwall 620to indicate to the practitioner the diameter of the drill bit 630 housedat each bore 624. In one embodiment, the planar endwall 620 alsoincludes one or more adapter holes 648 for receiving one or more socketadapters 650.

The holder 612 further includes a plurality of generally vertical slots660 extending through the generally annular sidewall 622 and a pluralityof indicia of depth 662 adjacent each vertical slot 660. In theembodiment shown, the annular sidewall 622 of the holder 612 includesone or more grip surfaces 664 to aid the practitioner in manipulatingthe holder 612. The annular sidewall 622 further includes a threadedinner surface 666, which may include, for example, a helical groove 668,for reasons discussed below.

The illustrated pedestal 614 includes a base 670 and a generallycylindrical shaft 672 projecting upward from the base 670 to an upperend 674. The base 670 may include one or more feet 676 (FIG. 27A) forsupporting the pedestal 614 on a surface, such as a table (not shown).The shaft 672 is configured for rotatably receiving the holder 612 suchthat the holder 612 is generally free to rotate on or relative to theshaft 672 so as to cause vertical movement of the holder 612 on orrelative to the shaft 672. To that end, the shaft 672 includes athreaded outer surface 680 for threadably engaging the threaded innersurface 666 of the annular sidewall 622 of the holder 612. For example,the threaded outer surface 680 may include a helical projection 682configured to engage the helical groove 668 of the threaded innersurface 666 of the holder 612. The interaction of the threaded outersurface 680 with the threaded inner surface 666 translates the turningmotion of the holder 612 relative to the shaft 672 into linear motion ofthe holder 612 relative to the shaft 672. For example, clockwiserotation of the holder 612 relative to the shaft 672 may move the holder612 in an upward direction relative to the shaft 672, andcounterclockwise rotation of the holder 612 relative to the shaft 672may move the holder 612 in a downward direction relative to the shaft672, or vice versa.

As shown, the drill limit system 610 further includes a platform 690rotatably positioned over the upper end 674 of the shaft 672 of thepedestal 614. The platform 690 may rest atop the shaft 672 below theendwall 620 of the holder 612 such that the platform 690 may begenerally vertically stationary with respect to the shaft 672. Thus,vertical movement of the holder 612 relative to the shaft 672 alsocauses vertical movement of the holder 612 relative to the platform 690.In this manner, rotation of the holder 612 relative to the shaft 672 mayset the variable depth of the holder 612 relative to the platform 690.

As shown, the platform 690 includes a generally circular top surface 692and a plurality of fingers extending radially outwardly from a peripheryof the top surface 692, including an engagement finger 694 and aplurality of marker fingers 696. The top surface 692 is generallyhorizontal and includes a plurality of recesses 700 configured toreceive the drill bits 630 at a uniform vertical position relative tothe platform 690. In this respect, each recess 700 generally verticallyaligns with a respective drill stop 632, such that each drill bit 630 isheld within the corresponding bore 624 of the holder 612 in a generallyvertical orientation and the tip of each drill bit 630 is positioned inthe corresponding recess 700. In one embodiment, the top surface 692further includes one or more adapter recesses 702 configured to receivecorresponding socket adapters 650.

The engagement finger 694 of the platform 690 is configured tomechanically engage a generally vertical channel 704 extending along thethreaded inner surface 666 of the annular sidewall 622 of the holder612, in order to cause the platform 690 to rotate with rotation of theholder 612 relative to the pedestal 614. In this regard, the platform690 includes a generally annular bearing surface 710 on an underside ofthe platform 690 opposite the top surface 692 for rotatably engaging theupper end 674 of the shaft 672 to enable the platform 690 to generallyfreely rotate on the shaft 672. In the embodiment shown, the shaft 672is hollow at least at or near the upper end 674, and the platform 690includes a generally circular protrusion 712 extending downward relativeto the top surface 692 such that the protrusion 712 is received in thehollow portion of the shaft 672 and opposes an interior wall of theshaft 672 to assist in centering the platform 690 relative to the shaft672. In one embodiment, the engagement finger 694 and vertical channel704 are each sized and shaped to provide a tight fit therebetween forprecise rotation of the platform 690 with the holder 612. It will beappreciated that by rotating the platform 690 with the rotation of theholder 612, the alignment of the recesses 700, 702 of the platform 690with the corresponding bores 624, 648 of the holder 612 is maintainedduring rotation of the holder 612. Thus, the drill bits 630 and/orsocket adapters 650 may remain in place in the drill limit system 610while the variable depth between the platform 690 and holder 612 is set.

The marker fingers 696 of the platform 690 are configured to extendthrough the vertical slots 660 of the holder 612 and align with thecorresponding indicia of depth 662 on the holder 612 to provide a visualindication of a current variable depth between the platform 690 and theholder 612. For example, as the holder 612 is rotated relative to theshaft 672, thereby adjusting the variable depth between the platform 690and holder 612, the indicia of depth 662 move vertically relative to therespective marker fingers 696, which remain generally verticallystationary. Thus, the alignment of a marker finger 696 with a particularindicia of depth 662 may correspond to a certain variable depth betweenthe platform 690 and holder 612.

As shown in FIG. 26, the drill limit system 610 includes a lid 720 whichmay be removably secured to the holder 612 over the planar endwall 620.The lid 720 includes a generally circular cover portion 722 and aplurality of locking tabs 724 extending downward at or near theperiphery of the cover portion 722. The locking tabs 724 are configuredto engage one or more features of the holder 612 in order to retain thelid 720 on the holder 612. In the embodiment shown, the locking tabs 724are configured to engage with upper portions of the vertical slots 660of the holder 612. In one embodiment, the locking tabs 724 may beconfigured to provide a snap-fit engagement with the vertical slots 660.In this regard, the locking tabs 724 and/or cover portion 722 maycomprise a semi-flexible material, such as a plastic material, so thatunder a sufficient force the locking tabs 724 may snap into place tosecure the lid 720 to the holder 612, and so that under a sufficientforce the locking tabs 724 may be unsnapped to remove the lid 720 fromthe holder 612. Apertures 726 may be provided in the lid 720 adjacentthe locking tabs 724 to provide flexibility thereto. In the embodimentshown, the planar endwall 620 of the holder 612 is positioned below, oroffset from, an upper end of the annular sidewall 622 to provide arecessed area 730 for containing the drill stops 632 and/or othercomponents when the lid 720 is secured to the holder 612. In thismanner, the lid 720 may prevent the drill stops 632 and/or othercomponents from being dislodged from the holder 612 and/or lost, such asduring transportation of the drill limit system 610.

With specific reference now to FIGS. 27A and 27B, to set the height ofthe drill stops 632 relative to the corresponding drill bits 630, thepractitioner rotates the holder 612 to the desired height as indicatedby aligning the marker fingers 696 of the platform 690 with theappropriate indicia 662 of the holder 612. For example, the practitionermay rotate the holder 612 from a first height (FIG. 27A) to a secondheight (FIG. 27B). In the embodiment shown, glide elements 732 radiallyextending from the circular protrusion 712 of the platform 690 ridealong the interior wall of the shaft 672 as the holder 612 is rotated tothe desired height setting. The glide elements 732 may be, for example,biased pins or ball bearings. A depth notch 734 is provided in the wallof the shaft 672 at or near the upper end 674, and is configured tointeract with the glide elements 732 to provide incremental tactileand/or audible indications that the height indicated by the markerfingers 696 and corresponding indicia of depth 662 has been reached. Forexample, having a single depth notch 734 and two oppositely disposedglide elements 732 as shown may provide for such indications at everyhalf-turn of the holder 612. However, the practitioner may rotate theholder 612 slightly more or slightly less to allow fine control of theheight of the drill stops 632 relative to the drill bits 630. Asdescribed above, as the holder 612 is rotated, the threadable engagementof the threaded inner surface 666 of the holder 612 with the threadedouter surface 680 of the shaft 672 raises or lowers the holder 612relative to the platform 690, which in turn raises or lowers the drillstops 632 relative to the drill bits 630.

Referring now to FIGS. 28A and 28B, once the desired height of a drillstop 632 has been set, the previously described torque-control tool 116may be used to secure the drill stop 632 to, or remove the drill stop632 from, the respective drill bit 630. In particular, the ratchet 179is coupled to one of the socket adapters 650 held by the holder 612and/or platform 690. In this regard, each of the socket adapters 650includes a connecting end 740, which includes a fitment 742 configuredto interact with the ratchet 179, and a torque end 744, which includes asocket 746 configured to interact with the nut portion 750 of one ormore of the drill stops 632.

With the torque-control tool 116 assembled, the socket 746 of the socketadapter 650 is positioned over the nut portion 750 of the drill stop632, as shown in FIG. 29. As the socket adapter 650 is turned, due tothe contact between the socket 746 and the flats 752 of the nut portion750, the movement causes turning of the nut portion 750 with the gripportion 642 remaining stationary due to its interaction with the recess626 of the holder 612. In addition or alternatively, spring clips and/orclip features similar to those described above may be used to retain thegrip portion 642 on the holder 612. In any event, the nut portion 750may tighten and loosen the grip portion 642 on the drill bit 630 in amanner similar to that described with respect to the above embodiments.

In one embodiment, the outer dimensions (e.g., the lengths of the flats752) of the nut portions 750 may be standardized such that multiple nutportions 750 have similar outer dimensions. Each of the socket adapters650 may be configured for use with a particular set of nut portions 750.For example, the sockets 746 of the socket adapters 650 may have innerdimensions similar to the outer dimensions of the corresponding set ofnut portions 750. In this manner, a single socket adapter 650 may besuitable for use with more than one drill stop 632. This may eliminatethe need for a dedicated socket adapter 650 or dedicated rotatablesocket drive adapter 167, 267, 480 for each individual drill stop 632.

Conveniently, the socket adapters 650 may be color coded to quicklyindicate to the practitioner the matching drill stop(s) 632.Additionally, a plurality of indicia such as lines 760 may be printed,etched, or otherwise included, proximate to the bores 624 and/orrecesses 626 of the endwall 620 of the holder 612 to indicate to thepractitioner the various drill stop(s) 632 corresponding to a particularsocket adapter 650. In the embodiment shown, the lines 760 visuallydivide the drill stops 632 into three sets, each set being proximate thesocket adapter 650 configured for use with that set of drill stops 632.However, it will be appreciated that any number of socket adapters 650may be supplied for any number of drill stops 632.

While the present invention has been illustrated by the description ofone or more embodiments thereof, and while the embodiments have beendescribed in considerable detail, they are not intended to restrict orin any way limit the scope of the appended claims to such detail. Forexample, the drill limit system has been described above with respect touse with a tooth and/or jawbone. However it will be appreciated that thedrill limit system may be used in any variety of medical procedures,such as an endodontic procedure. The various features shown anddescribed herein may be used alone or in any combination. Additionaladvantages and modifications will readily appear to those skilled in theart. The invention in its broader aspects is therefore not limited tothe specific details, representative apparatus and method andillustrative examples shown and described. Accordingly, departures maybe from such details without departing from the scope of the generalinventive concept.

What is claimed is:
 1. A drill limit system for providing a drill stopwith a drill bit, comprising: a holder including at least one drill stoppositioned on the holder and configured to receive at least one drillbit therethrough, wherein the at least one drill stop has a first statein which the at least one drill bit is configured to be movable relativeto the at least one drill stop and a second state in which the at leastone drill stop is configured to be secured to the at least one drillbit; and a platform operatively coupled to the holder and having asurface configured to engage a tip end of the at least one drill bit,wherein the holder and the platform are movable relative to each othersuch that the position of the at least one drill stop relative to the atleast one drill bit may be selectively varied in order to locate the atleast one drill stop at a desired position on the at least one drillbit, wherein the platform is configured to be vertically stationary andthe holder is configured to be movable relative to the platform.
 2. Thedrill limit system of claim 1, wherein rotation of the holder causesvertical movement of the holder relative to the platform.
 3. The drilllimit system of claim 2, wherein the holder includes one of a helicalgroove or a projection configured to interact with the other of ahelical groove or a projection, and wherein rotation of the holdercauses the projection to move along the helical groove to move theholder relative to the platform.
 4. The drill limit system of claim 3,further comprising: a shaft; wherein the holder includes one of thehelical groove or projection, and the shaft includes the other of thehelical groove or projection.
 5. The drill limit system of claim 3,wherein the projection follows a helical path.
 6. The drill limit systemof claim 2, wherein rotation of the holder causes the platform to rotatewith the holder.
 7. The drill limit system of claim 6, wherein theholder includes at least one generally vertical channel and the platformincludes at least one engagement finger configured to mechanicallyengage the at least one generally vertical channel when the holder isrotated.
 8. The drill limit system of claim 6, further comprising: ashaft including an inner wall and at least one notch on the inner wall;wherein the platform includes at least one glide element configured toride along the inner wall of the shaft during rotation of the platformand to interact with the at least one notch to provide incrementaltactile and/or audible indications of the position of the at least onedrill stop on the at least one drill bit.
 9. The drill limit system ofclaim 1, further comprising indicia for indicating the position of theat least one drill stop on the at least one drill bit.
 10. The drilllimit system of claim 9, wherein the holder includes at least onegenerally vertical slot adjacent the indicia, the platform includes atleast one marker finger configured to extend into the at least onegenerally vertical slot, and alignment of the at least one marker fingerwith the indicia indicates the position of the at least one drill stopon the at least one drill bit.
 11. The drill limit system of claim 1,further comprising: at least one stopper configured to limit movement ofthe holder relative to the platform.
 12. The drill limit system of claim1, wherein the at least one drill stop comprises: a nut portion; and agrip portion threadably coupled to the nut portion, wherein rotation ofthe nut portion relative to the grip portion transitions the drill stopbetween the first and second states.
 13. The drill limit system of claim12, wherein the holder includes a rotatable member configured to rotatethe nut portion relative to the grip portion.
 14. The drill limit systemof claim 12, wherein the at least one drill stop includes a firstplurality of drill stops and a second plurality of drill stops, thedrill stops being configured for use with respective drill bits havingdifferent diameters from each other, the drill limit system furthercomprising: first and second socket adapters, wherein the first socketadapter is configured to rotate the nut portions of the first pluralityof drill stops relative to the grip portions of the first plurality ofdrill stops, and wherein the second socket adapter is configured torotate the nut portions of the second plurality of drill stops relativeto the grip portions of the second plurality of drill stops.
 15. Thedrill limit system of claim 1, further comprising: a lid removablyattachable to the holder for securing the at least one drill stop on theholder.
 16. A method for attaching a drill stop to a drill bit,comprising: providing a holder and a platform movable relative to eachother, the holder including at least one drill stop positioned thereon;inserting at least one drill bit through at least one respective drillstop in the holder so that a portion of the at least one drill bitengages the platform; moving the holder relative to the platform whilemaintaining the platform vertically stationary to select a desiredheight of the at least one drill stop on the at least one respectivedrill stop; and engaging the at least one drill stop onto the respectiveat least one drill bit at the selected height.
 17. The method of claim16, wherein moving the holder relative to the platform includes rotatingthe holder.
 18. The method of claim 17, wherein rotating the holderincludes rotating the platform.
 19. The method of claim 16, furthercomprising: rotating a first portion of the at least one drill stoprelative to a second portion of the at least one drill stop to engagethe at least one drill stop onto the respective at least one drill bit.20. The method of claim 19, wherein the step of rotating the firstportion of the at least one drill stop relative to the second portion ofthe at least one drill stop includes rotating a rotatable member of theholder that is in contact with the first portion of the drill stop.